[0001] The invention relates to a chute, which suits primarily for supplying stone material
into a milling machinery. A supply chute according to the invention is typically used
in the concentrator of a mine.
[0002] Fig. 1 shows a principled drawing of the transfer system of stone material to a milling
machinery. A conveyer belt BEC of stone material STM, supply box SUB, supply chute
100 and milling machinery BAM are seen in the figure. The end of the conveyer belt
is located above the supply box so that the stone material carried by the belt drops
into the supply box.
[0003] The supply chute 100 is a wide pipe, which is mounted at a tilt e.g. at an angle
of 25 degrees. The upper end of the pipe extends through a hole in a wall of the supply
box SUB and the lower end is located inside the end of the milling machinery BAM.
When the upper level of the stone material STM accumulated in the supply box rises
above the lower surface of the upper end of the supply chute, the material dropping
into the supply box rolls into the supply chute and further along its inner surface
into the milling machinery.
[0004] Figs. 2a and
2b show an example of the known supply chute of stone material. Fig. 2a shows the supply
chute 200 as longitudinal section and Fig. 2b as seen from the lower end. The basic
part of the supply chute 200 is a supply pipe 210 made from a steel, the diameter
d of the pipe being in the order of 120 cm. The upper end of the pipe has been cut
as oblique so that its cross surface is vertical, when the chute is in the use position.
At the upper surface of the pipe there is a checking hatch 280 for watching the condition
of the chute.
[0005] The lower side of the inner wall of the supply pipe 210 has been coated by the steel
plates 231, 232, 233. In the example the plates are in five rows, three plates in
each row. The steel plates have been fastened on the pipe's wall by bolts 271, 272.
In the example each plate has been fastened by four bolts. After bolting the steel
plates further are welded together. By means of the steel plates it is implemented
wearing course in the supply pipe 210. Without them the stone avalanche would wear
its bottom so that the whole supply pipe should be replaced quite too often. When
the steel plates are very worn, the wearing course is renewed replacing only them,
not the pipe.
[0006] A drawback of the above-described structure is that the replacement or repair of
the steel plates of the chute requires much work and time. In addition, it has to
be done relatively often, in practice at six week intervals, which causes remarkable
labour costs and material costs. Further a drawback of the known structure is that
leaks begin to occur during the use at the fastening bolts of the steel plates of
the supply chute. This results in that the floor below the chute gets dirty, which
means continuous cleaning costs.
[0007] The object of the invention is to reduce said drawbacks of the prior art. An supply
chute according to the invention is characterized in what is set forth in the independent
claim 1. Some preferred embodiments of the invention are set forth in the other claims.
[0008] The basic idea of the invention is the following: A chute supplying stone material
into a mill machinery consists of a supply pipe, or outer pipe, and a rotatable, hard
wearing inner pipe inside it. The rotatableness is implemented by mounting the support
rollers with bearings under the inner pipe. During the use the inner pipe is fastened
to the outer pipe by the joints, which can be easily loosened. When they are loosened,
the inner pipe can be rotated on the support rollers. The slide of the inner pipe
downwards in the direction of its axis is stopped by side rollers, fastened to the
outer pipe, against which side rollers a flange fastened to the inner pipe presses.
The side rollers lightens for its part the rotating of the inner pipe. When the lower
surface inside the inner pipe has worn, a rotation with suitable angle is carried
out, in which case the wearing course is renewed.
[0009] The invention has the advantage that the maintenance costs of the supply chute are
for labour's part substantially lower than costs when the known chute technics is
used. This is due to that the rotation of the inner pipe, by which new wearing course
is arranged, is a simple and quick work and the need for the pipe maintenance through
its life is insignificant. In addition, the invention has the advantage that also
the material costs in the maintenance of the supply chute according to it are relatively
low. This is due to that the inner pipe itself acts as wearing material and the pipe
can be utilized wholly because of the rotation of the pipe. Then there is no need
to coat the inner pipe by a separate wearing material. Remarkable costs are caused
only when the whole inner pipe has to be replaced. Further the invention has the advantage
that no leaks occur in the supply chute according to it, the mill environment thus
keeping more clean.
[0010] In the following, the invention will be described in more detail. Reference will
be made in the description to the accompanying drawings, in which
- Fig. 1
- presents the principle of the transfer system of the stone material to be milled,
- Figs.2a,b
- present an example of the supply chute of stone material according to prior art,
- Fig. 3
- presents an example of the supply chute of stone material according to the invention,
- Fig. 4
- presents the supply chute in Fig. 3 seen from the lower end,
- Fig. 5
- shows an example of the locking way of the inner pipe of the supply chute according
to the invention,
- Fig. 6
- presents a detail of Fig. 5,
- Figs. 7a,b
- present the releasing of the inner pipe according to Fig. 5 from the locking,
- Fig. 8
- presents another example of the supply chute of stone material according to the invention,
and
- Fig. 9
- presents an example of the machine locking/releasing the inner pipe according to the
invention.
[0011] Fig. 3 shows an example of the supply chute of stone material, generally any wearing hard
material, according to the invention. The supply chute 300 has been drawn in its use
position, where its tilt angle is about 25 degrees. The supply chute 300 comprises
an outer pipe 310 and inner pipe 320. For rolling the inner pipe, the outer pipe is
two-part: it has an upper pipe 311 and a lower pipe 312. The upper end of the upper
pipe has been cut oblique as the supply pipe in Fig. 2a so that its edge matches,
in the use position of the chute, the edge of the opening in the vertical wall of
the supply box. In the example of Fig. 3 the upper pipe 311 and lower pipe 312 are
fastened to each other by bolt joints. For these joints there are an upper flange
315 on the outer surface of the lower end of the upper pipe and correspondingly a
lower flange 316 on the outer surface of the upper end of the lower pipe, and holes
of the fastening bolts in these flanges. Two fastening bolts 351, 352 with their nuts
are drawn in the figure. The bolt joints are located with certain distances in the
circle of the flanges of the outer pipe, e.g. eight ones in all. Each bolt joint includes
a gap piece 355, which is pressed between the upper and lower flange. By these gap
pieces the distance between the upper and lower flange is set to be suitable. The
diameter of the outer pipe is e.g. 120 cm as the one of the supply pipe in Fig. 2.
[0012] The diameter of the inner pipe 320 is a little shorter than the one of the outer
pipe 310 so that a small distance, e.g. 10 mm, remains between them. The inner pipe
is for example of wear resistent steel or cast steel and the thickness of its wall
is e.g. 20-40 mm. The inner pipe is here cylindrical extending as mounted in the lower
part of the chute 300 to some extent outside both the upper and lower end of the outer
pipe. So the wear due to the stone material relates only to the inner pipe. On the
outer surface of the inner pipe 320 there is a push flange 325. In the ready structure
the push flange is located between the upper flange 315 and the lower flange 316.
The distance of these flanges is longer than the thickness of the push flange so that
the inner pipe can be a little moved in the direction of its axis. The diameter of
the push flange 325 is shorter than the diameter of the upper and lower flange so
that the bolts 351, 352 connecting the parts of the outer pipe 310 go over the push
flange without touching it.
[0013] The mounted inner pipe 320 rests on the support rollers with bearings, in order to
make possible to rotate the inner pipe in practice. In Fig. 3 it is seen two support
rollers 341, 343 beside the outer pipe; on the other side of the outer pipe there
are another two support rollers. The support rollers again are fastened in pairs,
the upper and lower pair, to the lower pipe 312 of the outer pipe by cradle mechanisms
371. In order to the support rollers could carry the inner pipe at each support roller
there is an opening OP1 in the lower pipe 312.
[0014] To the outer surface of the lower pipe 312 it has been fastened at least two side
rollers 345 with bearings so that their axes are directed towards the axis of the
inner pipe. Each side roller extends to the space between the upper flange 315 and
lower flange 316 through an opening (OP2, Fig. 4) in the lower flange, towards the
push flange 325 of the inner pipe. The aim of the side rollers appears from Figs.
7a,b and their description.
[0015] Fig. 4 shows the supply chute of Fig. 3 viewed from the lower end, in the direction of its
axis. The inner pipe 320, lower pipe 312 and the lower flange 316 of the outer pipe
fastened to the lower pipe are seen in the figure. Behind the lower flange there is
the push flange 325. On opposite sides of the lower flange there are two openings
OP2, in which the above-mentioned side rollers 345, 346 partly are located. The fastening
parts of the side rollers are not drawn for clarity. The lower roller pair 341, 342
of the support rollers of the inner pipe is seen. In the example the locations of
the support rollers are chosen so that in both pair the support points of the inner
pipe form about the straight angle with the pipe's axis in the cross section of the
pipe.
[0016] Fig. 4 shows also an example of the arrangement for rotating the inner pipe 320 by
hand. An oblong opening OP3 is both in the lower flange 316 and in the upper flange
at the corresponding places down. In the push flange 325, a part of which is seen
in the opening OP3, there are holes HL with suitable distances. When rotating the
inner pipe, a peg is put in a visible hole HL, extending also through the openings
OP3. From this peg it can then pull sidewards by skin or rope. The rotation stops
at the latest when said peg reaches the end of the openings OP3.
[0017] Fig. 5 shows an example of the locking parts and locking way of the inner pipe of a supply
chute according to the invention. In the figure there is as longitudinal section the
outer pipe 510 and inner pipe 520 of the supply chute, as in Fig. 3. Likeways, the
outer pipe has an upper flange 515 and lower flange 516, and the inner pipe has a
push flange 525 as in Fig. 3. For locking the inner pipe there are a certain amount
of threaded holes in the lower flange and locking bolts in these holes. Two locking
bolts 561, 562 are drawn in Fig. 5, the total number of them is for example eight.
[0018] Fig. 6 shows as magnified a detail of Fig. 5. There is drawn the locking position for part
of one locking bolt 561. This bolt has been screwed inwards so that it has butted
the push flange 525 against the upper flange 515. When all the locking bolts in the
circle of the lower flange are tightened in that way, the push flange is pressed for
its whole length against the upper flange, and the inner pipe will be fastened to
the outer pipe. The locking bolts have also a securing nut to be tightened against
the lower flange.
[0019] Figs. 7a,b show the releasing of the inner pipe according to Fig. 5 from the locking. In Fig.
7a the inner pipe 520 is in the locking state in accordance with Fig. 6, and in Fig.
7b it has been released. The releasing takes place so that all locking bolts 561 are
screwed open to some extent. In this case the inner pipe, owing to gravity, starts
sliding downwards in the direction of its axis. The movement stops, when the push
flange 525 presses against the side rollers 545 without touching the lower flange
516 of the outer pipe. In practice, the displacement of the inner pipe is a few millimeters.
When the inner pipe has been released, it is easy to rotate it by the power of man.
Without the side rollers the push flange 525 would bump against the lower flange 516,
in which case the rotating of the inner pipe would be heavy in spite of the support
rollers under the pipe.
[0020] When the inner pipe is rotated to a new position, new wearing course is naturally
obtained on its bottom. In practice a rotation is done e.g. at six week intervals,
and at a time it is rotated about 40 degrees. In this case the wearing course in the
inner pipe is enough about for a year, after which the whole inner pipe has to be
replaced. However, compared with prior art, the reduction in the material and especially
in the maintenance work is remarkable.
[0021] A more even wear and correspondingly more efficient material use is obtained, when
the inner pipe is rotated more frequently and a smaller angle at a time. In this case
the inner pipe makes more than one round during its useful life. In principle, the
rotation of the inner pipe can be also continuous, but the structure is then more
expensive.
[0022] Fig. 8 shows another example of the supply chute of stone material according to the invention.
The supply chute 800 has been drawn from the lower end, seen in the direction of the
chute's axis, as in Fig. 4. The outer pipe 810, the inner pipe 820 with the push flange
825 fastened to it and the upper flange 816 of the outer pipe are seen in the figure.
In the drawing the lower flange of the outer pipe has been removed from the front
of the push flange that this flange would be visible. Also the support rollers 841
and side rollers 845 according to the invention are seen in the drawing.
[0023] In this example the edge of the push flange 825 is saw-toothed for rotating the inner
pipe 820 by machine. The force required is generated by a linear actuating element
AR1, which is in a firm connection to the outer pipe. The actuating element can be
e.g. hydraulic or electric. The end of the shaft SFT of the actuating element is fitted
to the edge of the teeth of the push flange. One backward-and-forward movement of
the shaft rotates the push flange and at the same time the inner pipe 820 by the length
of a tooth.
[0024] In
Fig. 9 there is an example of the machine locking/releasing the inner pipe according to
the invention. The drawing shows one pressing point of the push flange 825 of the
inner pipe 820, as Fig. 6. Instead of the locking bolts the structure comprises now
linear actuators AR2 fastened to the lower pipe 812, and instead of the threaded holes
there are even and slippery holes with certain distances in the lower flange 816.
Each actuator comprises a rod, the outer end of which butts in one work position the
push flange and is in the other work position in said hole of the lower flange. The
actuators AR2 together generate an adequate force to press the push flange 825 firmly
against the upper flange 815. The number of the actuators in the circle is e.g. four
to eight. They can be hydraulic or made by another principle. These actuators have
a shared controller CTR. The controller further can be shared also with an actuator
AR1 in accordance with Fig. 8. In this case the releasing, rotation and re-locking
of the inner pipe take place for example by a couple of turns of switches.
[0025] In this description and claims the qualifiers "upper" and "lower" refer only to the
use position of the supply chute, not its storing or transport position.
[0026] A supply chute of stone material according to the invention has been described above.
However, its structure can differ from that presented. For example the parts of the
outer pipe can be connected to each other by means of, instead of the bolts, e.g.
welded pieces, which are cut off when needed. The outer pipe can also be continuous
without any flanges, in which case the inner pipe is held in its position and rotated
by an equipment fastened on the outer surface of the outer pipe. The inventive idea
can be applied in different ways within the scope set by the independent claim 1.
1. A supply chute (300; 500; 800) of wearing material, which comprises a supply pipe
to be mounted in a oblique position and an arrangement for renewing of wearing course
inside the supply pipe,
characterized in that said supply pipe is an outer pipe (310; 510; 810) in structure of the supply chute,
and said arrangement for renewing of wearing course comprises
- an inner pipe (320; 520; 820), the outer diameter of which is shorter than the inner
diameter of the outer pipe
- support rollers (341-344) with bearings fastened to the outer pipe (310; 510; 810)
under the inner pipe to make possible its rotating
- a structure (325; 825, OP2, 345, 346; 845, OP3, HL; AR1, SFT) for rotating the inner
pipe (320; 520; 820) and
- locking parts (561, 562; AR2) for holding the inner pipe in a certain locking state
and for releasing from it.
2. A supply chute according to claim 1,
characterized in that
- the outer pipe comprises an upper pipe (311; 511; 811) with an upper flange (315;
515; 815) on outer surface of its lower end and a lower pipe (312; 512; 812) with
a lower flange (316; 516; 816) on outer surface of its upper end, which upper and
lower pipes are connected to each other through the upper and lower flanges so that
a gap with a certain width is between the upper and lower flanges, and
- on outer surface of the inner pipe (320; 520; 820) there is a push flange (325;
525; 825), which is located between the upper flange (315; 515; 815) and the lower
flange (316; 516; 816), the thickness of the push flange being shorter than the width
of said gap between the upper and lower flanges.
3. A supply chute according to claim 2, characterized in that the upper pipe (311; 511) and lower pipe (312; 512) are connected to each other by
fastening bolts (351, 352), each bolt going through a hole in the upper (315; 515)
flange and in the lower flange (316; 516), and a gap piece (355) is located at each
fastening bolt between the upper and lower flanges to set the width of said gap between
the upper and lower flanges, when the fastening bolts press the upper and lower flanges
towards each other.
4. A supply chute according to claim 2,
characterized in that said structure for rotating the inner pipe (320; 520; 820) comprises
- at least two side rollers (345, 346; 545; 845) with bearings fastened to the outer
surface of the lower pipe (312; 512; 812) of the outer pipe, the axis of each side
roller being directed towards the axis of the inner pipe, and
- an opening (OP2) in the lower flange (316; 516; 816) at each side roller, through
which opening one side roller extends to the space between the upper (315; 515; 815)
and lower (316; 516; 816) flange so that the push flange (325; 525; 825) in said space
is pressed against the side rollers (345, 346; 545; 845) when the inner pipe is released
from said locking state.
5. A supply chute according to claim 4, characterized in that said structure for rotating the inner pipe (320) further comprises an oblong opening
(OP3) both down in the lower flange (316) and in the upper flange (315) and holes
(HL) with suitable distances in the push flange (325) to pull the inner pipe sidewards
from a peg put through one hole (HL) and said oblong openings (OP3).
6. A supply chute according to claim 4, characterized in that the edge of the push flange (825) is saw-toothed, and said structure for rotating
the inner pipe (820) further comprises an actuating element (AR1) in a firm connection
to the outer pipe, the actuating element having a shaft (SFT), which is arranged to
do linear backward-and-forward movements, an end of which shaft fits to the edge of
a teeth of the push flange.
7. A supply chute according to claim 2, characterized in that in the lower flange (516) there are with certain distances threaded holes, and said
locking parts comprise locking bolts (561, 562), each locking bolt being in a threaded
hole, to butt the push flange (525) against the upper flange (515) and release it
by screwing the locking bolts.
8. A supply chute according to claim 2, characterized in that in the lower flange (816) there are with certain distances even holes, and said locking
parts comprise at each even hole an actuator (AR2) fastened to the lower pipe (812)/the
lower flange (816), which actuator has a rod extending to said hole, the outer end
of which rod being arranged to butt in one work position the push flange (825) against
the upper flange (815) and to be in the other work position in said even hole of the
lower flange.
9. A supply chute according to claims 6 and 8, characterized in that said actuating element (AR1) and actuators (AR2) are hydraulic.
10. A supply chute according to claims 6 and 8, characterized in that said actuating element (AR1) and actuators (AR2) have a shared controller (CTR).
Amended claims in accordance with Rule 137(2) EPC.
1. A supply chute (300; 500; 800) for wearing material, which chute is intended to be
mounted in an oblique position and comprises
- an outer pipe (310; 510; 810)
- an inner pipe (320; 520; 820) for renewing of wearing course inside the supply chute,
the outer diameter of the inner pipe being shorter than the inner diameter of the
outer pipe and
- locking parts (561, 562; AR2) for holding the inner pipe in a certain locking state
and for releasing from it,
characterized in that said supply chute (300; 500; 800) further comprises
- support rollers (341-344) with bearings fastened to the outer pipe (310; 510; 810)
under the inner pipe to make possible its rotating and
- a structure (325; 825, OP2, 345, 346; 845, OP3, HL; AR1, SFT) for rotating the inner
pipe (320; 520; 820).
2. A supply chute according to claim 1,
characterized in that
- the outer pipe comprises an upper pipe (311; 511; 811) with an upper flange (315;
515; 815) on outer surface of its lower end and a lower pipe (312; 512; 812) with
a lower flange (316; 516; 816) on outer surface of its upper end, which upper and
lower pipes are connected to each other through the upper and lower flanges so that
a gap with a certain width is between the upper and lower flanges, and
- on outer surface of the inner pipe (320; 520; 820) there is a push flange (325;
525; 825), which is located between the upper flange (315; 515; 815) and the lower
flange (316; 516; 816), the thickness of the push flange being shorter than the width
of said gap between the upper and lower flanges.
3. A supply chute according to claim 2, characterized in that the upper pipe (311; 511) and lower pipe (312; 512) are connected to each other by
fastening bolts (351, 352), each bolt going through a hole in the upper (315; 515)
flange and in the lower flange (316; 516), and a gap piece (355) is located at each
fastening bolt between the upper and lower flanges to set the width of said gap between
the upper and lower flanges, when the fastening bolts press the upper and lower flanges
towards each other.
4. A supply chute according to claim 2,
characterized in that said structure for rotating the inner pipe (320; 520; 820) comprises
- at least two side rollers (345, 346; 545; 845) with bearings fastened to the outer
surface of the lower pipe (312; 512; 812) of the outer pipe, the axis of each side
roller being directed towards the axis of the inner pipe, and
- an opening (OP2) in the lower flange (316; 516; 816) at each side roller, through
which opening one side roller extends to the space between the upper (315; 515; 815)
and lower (316; 516; 816) flange so that the push flange (325; 525; 825) in said space
is pressed against the side rollers (345, 346; 545; 845) when the inner pipe is released
from said locking state.
5. A supply chute according to claim 4, characterized in that said structure for rotating the inner pipe (320) further comprises an oblong opening
(OP3) both down in the lower flange (316) and in the upper flange (315) and holes
(HL) with suitable distances in the push flange (325) to pull the inner pipe sidewards
from a peg put through one hole (HL) and said oblong openings (OP3).
6. A supply chute according to claim 4, characterized in that the edge of the push flange (825) is saw-toothed, and said structure for rotating
the inner pipe (820) further comprises an actuating element (AR1) in a firm connection
to the outer pipe, the actuating element having a shaft (SFT), which is arranged to
do linear backward-and-forward movements, an end of which shaft fits to the edge of
a teeth of the push flange.
7. A supply chute according to claim 2, characterized in that in the lower flange (516) there are with certain distances threaded holes, and said
locking parts comprise locking bolts (561, 562), each locking bolt being in a threaded
hole, to butt the push flange (525) against the upper flange (515) and release it
by screwing the locking bolts.
8. A supply chute according to claim 2, characterized in that in the lower flange (816) there are with certain distances even holes, and said locking
parts comprise at each even hole an actuator (AR2) fastened to the lower pipe (812)/the
lower flange (816), which actuator has a rod extending to said hole, the outer end
of which rod being arranged to butt in one work position the push flange (825) against
the upper flange (815) and to be in the other work position in said even hole of the
lower flange.
9. A supply chute according to claims 6 and 8, characterized in that said actuating element (AR1) and actuators (AR2) are hydraulic.
10. A supply chute according to claims 6 and 8, characterized in that said actuating element (AR1) and actuators (AR2) have a shared controller (CTR).